Thread protector for use with sucker rods and oil tools

Abstract

A thread protector for use on a sucker rod or a drill pipe has a collet with a plurality of collet segments in which each of the plurality of collet segments has a protrusion adjacent an end thereof, and a sleeve overlying the collet and movable between a first position and a second position. The second position compresses the plurality of collet segments such that the protrusion engages with the thread relief of the sucker rod or drill pipe. This retains the sleeve and the plurality of collet segments over the threaded end of the pipe so as to protect the threaded end of the pipe. The sleeve is movable to the first position such that the protrusions of the plurality of collet segments release from the thread relief so as to allow the thread protector to be removed from the threaded end of the pipe.

Claims

1. A thread protector for use on a sucker rod or tool, the sucker rod or tool having at least one externally threaded end and a thread relief adjacent the externally threaded end, the thread protector comprising: a collet having a plurality of collet segments, each of said plurality of collet segments having a protrusion adjacent an end thereof; and a sleeve overlying said collet and movable between a first position and a second position, the second position compressing the plurality of collet segments such that the protrusions engage with the thread relief of the sucker rod or drill pipe, said sleeve having a first section overlying an outer surface of said main body portion, said first section of said sleeve having an inner diameter slightly greater than an outer diameter of said main body portion, said sleeve having a second section extending from said first section, said second section having an inner diameter greater than the inner diameter of said first section, said second section overlying said plurality of collet segments, the sucker rod or drill pipe having a flange formed at a side of the thread relief opposite the thread, said sleeve having a third section having an inner diameter greater than the inner diameter of said second section, said third section overlying the flange when said sleeve is in the second position, said inner diameter of said third section being smaller than an outer diameter of said flange.

2. The thread protector of claim 1, said collet having a main body portion, said plurality of collet segments extending outwardly of said main body portion.

3. The thread protector of claim 2, said sleeve overlying said main body portion when in the first position.

4. The thread protector claim 2, said collet having an interior cavity adapted to receive the end of the sucker rod or drill pipe therein.

5. The thread protector claim 2, said protrusion being formed at an end of the collet segment opposite the main body portion.

6. The thread protector claim 2, said main body portion having a shoulder formed at an outer surface thereof, said sleeve residing against said shoulder in the first position.

7. The thread protector claim 2, said main body portion of said collet having an O-ring positioned in a groove formed therein.

8. The thread protector of claim 1, the protrusion having an inner portion and an outer portion, the inner portion of the protrusion protruding inwardly of an inner surface of the collet segment, said outer portion of the protrusion protruding outwardly of an outer surface of the collet segment.

9. The thread protector of claim 1, the inner diameter of said second section being less than an outer diameter of said collet at the protrusions.

10. A protector assembly comprising: a sucker rod having an external thread at an end thereof and a thread relief adjacent to the external thread, said sucker rod having a greater outer diameter at the external thread than at the thread relief; a collet having a plurality of collet segments, each of said plurality of collet segments having a protrusion adjacent an end thereof; and a sleeve overlying said collet and rotatable between a first position and a second position, the second position compressing said plurality of collet segments such that the protrusion engages with the thread relief of said sucker rod.

11. The protector assembly of claim 10, said collet having a main body portion, said plurality of collet segments extending outwardly of said main body portion.

12. The protector assembly of claim 11, said sleeve overlying said main body portion when in the first position.

13. The protector assembly of claim 11, said main body portion having a shoulder formed at an outer surface thereof, said sleeve residing against said shoulder when in the first position.

14. The protector assembly of claim 11, said main body portion of said collet having an O-ring positioned in a groove formed therein.

15. The protector assembly of claim 11, said sleeve having a first section overlying an outer surface of said main body portion, said first section of said sleeve having an inner diameter slightly greater than an outer diameter of said main body portion, said sleeve having a second section extending from said first section, said second section having an inner diameter greater than the inner diameter of said first section, said second section overlying said plurality of collet segments.

16. The protector assembly of claim 15, the inner diameter of said second section being less than an outer diameter of said collet at the protrusions thereof, said sucker rod having a flange formed to the side of said thread relief opposite said thread, said sleeve having a third section having an inner diameter greater than the inner diameter of said second section, said third section overlying the flange when said sleeve is in the second position.

17. The protector assembly of claim 10, the protrusion of said collet having an inner portion and an outer portion, said inner portion protruding inwardly of an inner surface of the collet segment, said outer portion protruding outwardly of an outer surface of the collet segment.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) FIG. 1 is a perspective view of a sucker rod of the prior art showing, in particular, the externally threaded end of the sucker rod.

(2) FIG. 2 is a cross-sectional view of a prior art thread protector.

(3) FIG. 3 is a side elevational view of the thread protector of the present invention as applied over the end of the sucker rod.

(4) FIG. 4 is a cross-sectional view showing the thread protector of the present invention as applied over the threads of the sucker rod in which the sleeve is in a first position.

(5) FIG. 5 is a cross-sectional end view of the thread protector of the present invention showing, in particular, the sleeve as compressing the collet segments.

(6) FIG. 6 is a cross-sectional end view showing the sleeve as releasing the plurality of collet segments and for the release of the sucker rod from the thread protector.

(7) FIG. 7 is a side elevational view of the thread protector of the present invention with the sleeve in a second position for locking the thread protector onto the threads of the sucker rod.

(8) FIG. 8 is a cross-sectional view of FIG. 7 showing, in particular, the locking of the collet segments onto the thread relief of the sucker rod.

(9) FIG. 9 is a cross-sectional view of an alternative embodiment of the thread protector of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

(10) FIG. 3 shows the thread protector 30 in accordance with the preferred embodiment of the present invention. The thread protector 30 includes a collet 32 and a sleeve 34 extending over the collet 32 and over the exterior of the sucker rod or oil tool 36. In particular, in FIG. 3, the collet 32 includes a main body portion (shown in FIG. 4 as reference number 35) of a generally cylindrical shape that is adapted to receive the threaded end of the sucker rod 36 therein. The sleeve 34 is configured so as to be positioned over this main body portion.

(11) The sleeve 34 includes a first section 38 which extends over the outer diameter of the main body portion of the collet 32. As will be described hereinafter, the inner diameter of the first section 38 will be only slightly greater than the outer diameter of the main body portion so that the first section 38 can slide with respect to the outer diameter of the main body portion. A second section 40 extends from the first section 38 and has an outer diameter greater than the outer diameter of the first section 38. A third section 42 extends from the second section 40 and has an outer diameter which is greater than the outer diameter of the second section 40. Generally, the third section 42 will reside over the flange 56 of the sucker rod 36.

(12) FIG. 4 shows the internal configuration of the collet 32 with respect to the sleeve 34. The collet 32 has the main body portion 35 extending outwardly therefrom. The sleeve 34 is shown in its first position in which the plurality of collet segments 44 of collet 32 are flexed outwardly. This outward flex is the natural orientation of the plurality of collet segments 44 when not under pressure or tension. Each of the plurality of collet segments 44 includes a protrusion 46. It can be seen that protrusion 46 is located in the area of the thread relief 48 beyond the externally threaded end 50 of the sucker rod 36.

(13) In FIG. 4, it can be seen that the sleeve 34 has an end generally adjacent to the shoulder 54 of the main body portion 35 of collet 32. As such, when the sleeve 34 is in this retracted position, no or minimal pressure is applied to the outer surfaces of either the plurality of collet segments 44 and the protrusions 46 by the interior surfaces of the sleeve 34.

(14) The first section 38 of sleeve 34 is illustrated as having an inner diameter only slightly greater than the outer diameter of the main body portion 35 of collet 32. The collet segments 44 extend outwardly from the main body portion 35. The interior of the plurality of collet segments 44 form an area for the receipt of the externally threaded end 50 of the sucker rod 36.

(15) The second section 40 of the sleeve 34 extends from the first section 38. The second section 40 has an inner diameter that is greater than the outer diameter of the plurality of collet segments 44 and also greater than the inner diameter of the first section 38. The third section 42 of the sleeve 34 is illustrated as having an inner diameter greater than the outer diameter of the plurality of protrusions 46. The inner diameter of the third section 42 is preferably slightly smaller than the outer diameter of the flange 56 of the sucker rod 36, which creates an interference fit and forms a seal.

(16) In this initial installation procedure, the plurality of collet segments 44, along with the sleeve 34, can be placed over the externally threaded end 50 of the sucker rod 36. This insertion procedure can continue until the end of the third section 42 of the sleeve 34 overlies the flange 56. As such, it can be assured that the threaded end 50 is properly nested within the interior of the collet 32 and interior of the plurality of collet segments 44. In order to lock the collet 32 over the externally threaded end 50 of the sucker rod 36, it is only necessary to push the sleeve 34 away from the main body portion 35 of the collet 32 in a direction toward the flange 56 of the sucker rod 36. This will lock the plurality of collet segments 44 and associated protrusions 46 in a position within the thread relief 48 of the sucker rod 36.

(17) FIG. 4 also shows an O-ring-70 provided on the collet 32. The O-ring 70 is positioned in a groove formed in the main body portion 35 of the collet 32. Preferably, the O-ring 70 and groove are positioned slightly inwardly of the plurality of protrusions 46 of the collet 32. The O-ring 70 is compressible and abuts the inner diameter of the sleeve 34. The O-ring 70 provides for an interference fit and seal between the collet 32 and the sleeve 34. Further, the O-ring 70 provides a resistance between the collet 32 and the sleeve 34 which provides for easy installation of the thread protector of the present invention. In other embodiments, the O-ring 70 could be provided on the inner surface of the sleeve 34.

(18) FIG. 5 shows this locked configuration of the sleeve 34 over the protrusions 46 of the plurality of collet segments 44. The protrusions 46 are compressed together so that the sides of each of the protrusions 46 will be closely positioned against each other and so as to extend around the thread relief 48 of the sucker rod 36.

(19) FIG. 6 shows the separation of the protrusions 46 that results from the rearward movement of the sleeve 34. As can be seen, each of the plurality of collet segments 44 will move outwardly so as to correspondingly flex the protrusions 46 outwardly. As such, since the plurality of collet segments 46 are generally spaced further away from each other, this will create a wider opening 60 to the cavity 61 therein. As such, the externally threaded end 50 of the sucker rod 36 can be easily removed from the thread protector.

(20) FIG. 7 shows the thread protector 30 of the present invention wherein the sleeve 34 has been moved away from the collet 32. As can be seen, this movement of the sleeve 34 exposes more of the main body portion 35 of the collet 32. When shifting the sleeve 34 in place, a 90° twist of the collet 32 relative to the sleeve 34 can be utilized. This twisting locates the tabs 61 of the collet 32 in line with the notches 62 of the sleeve 34, and away from the flange elements 64 of the sleeve 34. This prevents the sleeve from traveling to the unlocked position.

(21) FIG. 8 shows the sleeve 34 in its extended position. In this extended position, the second section 40 of the sleeve 34 will abut the outer surface of the protrusion 46 so as to compress the collet segment 44 and the protrusion 46 inwardly. As such, the inner surface of the protrusion 46 will engage with the curvature 71 of the thread relief 48. This locks the collet 32 in the position over the externally threaded end 50 of the sucker rod 36. The third section 42 of sleeve 34 extends so as to overlie the flange 56 of sucker rod 36. In this configuration, the sleeve 34 and the collet 32 is locked over the externally threaded end 50 for protection. The present invention provides for a fluid tight fit, due in part to the O-ring 70 and the interference fit between the various components of the thread protector. The overlying relationship of the third section 42 of the sleeve 34 and the flange 56 provides further fluid resistance by interference fit.

(22) Referring to FIG. 9, there shown an alternative embodiment of the thread protector 100 of the present invention. The thread protector 100 is shown as being positioned over the end of a sucker rod or tool 102. The sucker rod or tool 102 has an externally threaded end 105 and a flange 103.

(23) The thread protector 100 comprises a sleeve having an open end and a closed end, and interior 104. The sleeve of the thread protector 100 has a first protrusion 106. The first protrusion 106 is received in a seat in the sucker rod or oil tool 102, and locks the thread protector 100 against the sucker rod or tool 102.

(24) The thread protector 100 additionally includes a second protrusion 108. The second protrusion 108 and has an inner diameter which is slightly smaller than the outer diameter of the flange 103. As such, the second protrusion 108 maintains an interference fit against the flange 103, and seals the thread protector 100 against the sucker rod or tool 102.

(25) A grip 110 is also provided on the closed end of the thread protector 100. This enables the thread protector 100 to be easily pushed on or pulled off of the sucker rod or oil tool 102. The thread protector 100 of the alternative embodiment of the present invention is formed of a semi-flexible material such that it can be easily snap on and pulled out of position on the sucker rod or oil tool 102.

(26) The foregoing disclosure and description of the invention is illustrative and explanatory thereof. Various changes in the details of the illustrated construction can be made within the scope of the appended claims without departing from the true spirit of the invention. The present invention should only be limited by the following claims and their legal equivalents.